328 AMERICAN SPIDERS AND THEIR SPINNINGWORK. 
If we turn to the Tubeweavers we find a varied and interesting field 
of spinning industry in the making of snares, nests, and cocoons. In all 
of these it may be confidently said that the methods, as far as known, 
are substantially the same as those described as prevail- 
ing in other tribes. A few illustrations show this fact. 
The interesting and well known water spider 
of Europe, Argyroneta aquatica, weaves in 
water a bell shaped tent (Fig. 314), within 
which she dwells, deposits her ege sac, and 
rears her young. ‘The following observation indicates 
Fic. 314, The bell shapea that even in this seemingly unnatural element the 
the water siden tnaer Same general method characterizes the spider’s weay- 
water. ing. Fig. 315 represents a patch of spinningwork 
made by this water spider upon a glass within which she was confined, 
and drawn by Mr. Underhill.t On examining the central part of this 
patch, it appeared, both to the naked eye and to the microscope, like 
a piece of the spider’s cocoon. Certain broad threads at the edge of the 
patch at once explained the method by which this close and 
Methods 
of Tube- 
weavers. 
boa even texture was obtained. They are represented by Fig. 315, ¢, 
Spider as they appeared under the microscope. They seem to have been 
produced, as in the cases above described, by the spider erecting 
or placing, parallel to one another, a series of spinning tubes, which emitted 
separate and parallel threads, instead of lines directed towards one point. 
These bands Mr. Underhill supposed a 
to be the product of the anterior f ni 
spinnerets, while the other two . ) : \\ 
threads, a and B, are emitted by the 
posterior and middle spinnerets. ) (| j 
When Agalena neevia wishes to i) pe 
extend the borders of her sheet iat AG i 
like snare, she proceeds 
in the same way, carry- g : 
ing first various lines be- WA GAA 
yond the margin to the desired dis- * eG iP 
tance, which lines are stretched . 
across the foliage or other surface ¢ Ytjz3 
that forms the nest site. When 2 
the desired number of these lines Fic. 315. Highly magnified piece of the Water spider’s 
has been laid down, the Tube- web. a,a, BB, the single original or warp lines; ¢, c, ¢, 
weaver moves backward and for- the banded filaments forming the weft. 
ward over them, spinning out all the while a stream of silk, at the same 
time moving her long spinnerets up and down from the surface of the 
Agalena’s . 
Method. 
1 “Science Gossip,” 1875, page 134. 
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